Analog to digital converters are commonly used in many electronic applications in order to convert analog signals to digital signals. In real world, most data or signals are characterized by analog signals, for example, temperature, voice, light, pressure, and so forth. These analog signals, which are continuous in time and amplitude, are converted to digital signals that are discrete with respect to time and quantized with respect to amplitude by an ADC. The ADC architectures vary based on the end applications, cost, speed and resolution. Various types of ADCs include, for example, Flash ADC, Delta-sigma ADC, Successive approximation type ADC and dual slope ADC.
Modern temperature sensors use high performance ADCs to accurately convert an analog measurement of temperature into digital data that may be used for further processing. When designing a high performance ADC, various attributes that may be taken into account include, for example, resolution, speed, silicon area, noise, and frequency of operation. Various errors may be introduced during an analog to digital conversion of a temperature signal. The errors may include, for example, gain error of the ADC, noise coupling, and mismatch between various components inside the ADC. Calibration of the ADC is one of various ways to minimize such errors.